Hall effect of epitaxial double-perovskite Sr_2FeMoO_6 thin films

TL;DR

This study investigates the electrical and magnetic properties of epitaxial Sr_2FeMoO_6 thin films, revealing electron-like and hole-like Hall effects, temperature-dependent resistivity, and complex transport behaviors.

Contribution

It provides detailed measurements of Hall effects and resistivity in Sr_2FeMoO_6 thin films, highlighting their unique charge transport characteristics compared to manganites.

Findings

Electron-like ordinary Hall effect observed.

Negative magnetoresistance at low temperatures.

Variable range hopping transport above 100 K.

Abstract

We prepared high epitaxial thin films of the compound Sr_2FeMoO_6 with narrow rocking curves by pulsed laser deposition. The diagonal and nondiagonal elements of the resistivity tensor were investigated at temperatures from 4 K up to room temperature in magnetic fields up to 8 T. An electronlike ordinary Hall effect and a holelike anomalous Hall contribution are observed. Both coefficients have reversed sign compared to the colossal magnetoresistive manganites. We found at 300 K an ordinary Hall coefficent of -1.87x10^{-10} m^3/As, corresponding to a nominal charge carrier density of four electrons per formula unit. At low temperature only a small negative magnetoresistance is observed which vanishes at higher temperatures. The temperature coefficient of the resistivity is negative over the whole temperature range. A Kondo like behavior is observed below 30 K while above 100 K variable range hopping like transport occurs.